In conventional rails for doors, the track rail body on which the door wheels run and the load support member which attaches the rail body to a building are formed in a single piece, and these rails were installed in the buildings via this load support member by engaging devices such as bolts. These rails for doors are made of material which is harder than materials for wheels of the doors to avoid wear, and generally, extruded aluminum materials and steel materials are used.
However, regarding the above-mentioned conventional rails for doors, in the case that the track rail body which directly contacts the door wheels need be replaced, because the entire track rail including load support member must be replaced, there were disadvantages not only in that the replacement task became large-scaled, but also in that the cost for the replacement was also high.
There was also a disadvantage in that doors with this type of rail structure are not appropriate for use, particularly in wards where the quietude is required such as hospitals, residential areas, offices, etc., because vibrations made by the running of the door wheels are directly transmitted through to the building.
This invention was made in order to overcome these disadvantages, and objects of the inventions are to make replacing the track rail body more efficient and to lower the cost. In addition, an object of the invention is to avoid the vibrations made by the running door wheels being transmitted through to the building, etc.